diff --git a/apps/federatedfilesharing/lib/FederatedShareProvider.php b/apps/federatedfilesharing/lib/FederatedShareProvider.php
index e3731ac3ecf..8a2c12e0ac8 100644
--- a/apps/federatedfilesharing/lib/FederatedShareProvider.php
+++ b/apps/federatedfilesharing/lib/FederatedShareProvider.php
@@ -431,13 +431,7 @@ class FederatedShareProvider implements IShareProvider, IShareProviderSupportsAl
 		return $share;
 	}
 
-	/**
-	 * Get all children of this share
-	 *
-	 * @param IShare $parent
-	 * @return IShare[]
-	 */
-	public function getChildren(IShare $parent) {
+	public function getChildren(IShare $parent): array {
 		$children = [];
 
 		$qb = $this->dbConnection->getQueryBuilder();
diff --git a/apps/sharebymail/lib/ShareByMailProvider.php b/apps/sharebymail/lib/ShareByMailProvider.php
index 16a13786ea1..d28f7c51327 100644
--- a/apps/sharebymail/lib/ShareByMailProvider.php
+++ b/apps/sharebymail/lib/ShareByMailProvider.php
@@ -637,11 +637,6 @@ class ShareByMailProvider extends DefaultShareProvider implements IShareProvider
 		return $token;
 	}
 
-	/**
-	 * Get all children of this share
-	 *
-	 * @return IShare[]
-	 */
 	public function getChildren(IShare $parent): array {
 		$children = [];
 
diff --git a/build/psalm-baseline.xml b/build/psalm-baseline.xml
index 44e54ae7f54..929f4ac015e 100644
--- a/build/psalm-baseline.xml
+++ b/build/psalm-baseline.xml
@@ -4261,9 +4261,6 @@
     <UndefinedClass>
       <code><![CDATA[\OCA\Circles\Api\v1\Circles]]></code>
     </UndefinedClass>
-    <UndefinedInterfaceMethod>
-      <code><![CDATA[getChildren]]></code>
-    </UndefinedInterfaceMethod>
   </file>
   <file src="lib/private/Share20/ProviderFactory.php">
     <InvalidReturnStatement>
diff --git a/lib/private/Share20/DefaultShareProvider.php b/lib/private/Share20/DefaultShareProvider.php
index a2c0fd15eb4..db62dfc0933 100644
--- a/lib/private/Share20/DefaultShareProvider.php
+++ b/lib/private/Share20/DefaultShareProvider.php
@@ -358,14 +358,7 @@ class DefaultShareProvider implements IShareProviderWithNotification, IShareProv
 		return $share;
 	}
 
-	/**
-	 * Get all children of this share
-	 * FIXME: remove once https://github.com/owncloud/core/pull/21660 is in
-	 *
-	 * @param \OCP\Share\IShare $parent
-	 * @return \OCP\Share\IShare[]
-	 */
-	public function getChildren(\OCP\Share\IShare $parent) {
+	public function getChildren(IShare $parent): array {
 		$children = [];
 
 		$qb = $this->dbConn->getQueryBuilder();
diff --git a/lib/private/Share20/Manager.php b/lib/private/Share20/Manager.php
index 9bfa810b108..eeaae7bbde0 100644
--- a/lib/private/Share20/Manager.php
+++ b/lib/private/Share20/Manager.php
@@ -1008,7 +1008,6 @@ class Manager implements IManager {
 
 	/**
 	 * Delete all the children of this share
-	 * FIXME: remove once https://github.com/owncloud/core/pull/21660 is in
 	 *
 	 * @param IShare $share
 	 * @return IShare[] List of deleted shares
diff --git a/lib/public/Share/IShareProvider.php b/lib/public/Share/IShareProvider.php
index 9d7c8013a36..23187ca833e 100644
--- a/lib/public/Share/IShareProvider.php
+++ b/lib/public/Share/IShareProvider.php
@@ -208,4 +208,12 @@ interface IShareProvider {
 	 * @since 18.0.0
 	 */
 	public function getAllShares(): iterable;
+
+	/**
+	 * Get all children of this share
+	 *
+	 * @return IShare[]
+	 * @since 9.0.0
+	 */
+	public function getChildren(IShare $parent);
 }